Separable connectors are typically employed to interconnect sources of energy, such as electrical distribution network conductors, to localized distribution components, such as switchgears and transformers. These connectors, for example, typically include a bushing insert, which is mounted in the bushing well of the switchgear, and an elbow connector which is releasably connected to the bushing insert on one end and a distribution conductor, such as a high voltage cable, of the network circuit feeding the switchgear. When the elbow is interconnected to the bushing, the switchgear is thus interconnected into the distribution network and thereby energized. Likewise, if the elbow is removed, the switchgear is disconnected from the distribution network and the switchgear is de-energized.
As part of the connection process, the elbow connectors are typically attached to an above ground or underground power cable. In order to attach the cable to the elbow connector, the protective layers of the cable, including the concentric neutrals that provide a path of return for the electrons in an alternating current system, must be removed, or peeled back, from a portion of the cable so that the conductor portion of the cable may be attached to the elbow connector. While a portion of the exposed cable is positioned within the elbow connector, another portion of the exposed cable is left outside of the elbow connector and could be exposed to the elements. The concentric neutrals are particularly at risk and tend to decay rapidly when exposed to moisture. Moisture causes the concentric neutrals to oxidize and corrode. After a certain level of corrosion has built up, the cable needs to be replaced because the return path for the electrons has been permanently disrupted. While the exposed portions of the cable are at risk for decay and damage due to exposure to water and other elements, unexposed portions of the cable are also at risk. For example, water that reaches and contacts the concentric neutrals of the exposed portion of the cable can be wicked away from the point of contact to other areas miles away from the exposed portion of the cable, causing corrosion and failure of the concentric neutrals along long sections of cable.
In order to protect the cable at the connection point with the elbow and other connectors, cable jacket sleeves were created. The cable jacket sleeves had a generally hollow cylindrical shapeand came in three primary varieties: pre-molded slide-on, heat shrink, and cold shrinkable. Heat shrink sleeves were placed over the exposed portion of the cable as described below. The lineperson would then use a blowtorch or other heat source to shrink the sleeve around the exposed portion of the cable to create a tighter seal.
Cold shrinkable sleeves are pre-expanded and placed onto a removable core. After the cold shrinkable sleeve is placed over the cable joint, the core is removed and the sleeve shrinks back to its original size, sealing the joint. Pre-molded slide-on sleeves have typically have to be lubricated to reduce the friction created by the tight interference fit required to seal the joint and are manually pushed or pulled onto the cable by a lineperson. Pre-molded slide-on sleeves generally require more steps and force to install, but are simpler and cheaper to manufacture than the other sleeve varieties.
Pre-molded slide-on jacket sleeves required a lineperson to place the seal on the cable prior to attaching the elbow connector. Once the elbow connector was attached to the cable, mastic and/or electrical tape was placed over the exposed portion of the cable and the jacket sleeve had to be pulled back up the cable and across the mastic until it covered the exposed portion of the cable and a portion of the elbow connector. Small tabs were added along both ends of some of the pre-molded slide-on sleeves to assist a lineperson in pulling the sleeve up and down the cable body. When completing the attachment of several connectors to cables, the multiple steps of pulling the sleeve down onto the cable and then pulling it back up the cable once the elbow connector was attached greatly increased the time and effort needed to properly protect the cable.
In order to reduce the time necessary to attach a cable to an elbow connector and properly protect the exposed portions of the cable with a sleeve, and to reduce the overall cost of the sleeve and elbow connector, a conventional combination sleeve and elbow connector has been created. The combination creates an integral jacket sleeve along the portion of the elbow connector to which the cable is attached. The combination is made by molding the elbow connector and the jacket sleeve together, at the same time and from the same material, thereby reducing cost and manufacturing time. In addition, since the jacket sleeve is integrally built into the elbow connection, once a lineperson has attached a cable, he or she need only pull the jacket sleeve in one direction, down over the exposed portion of the cable. In order to assist the lineperson in grasping and pulling the cable, two small tabs have been added to and extend longitudinally from the jacket sleeve.
Unfortunately, the combination jacket sleeve and elbow connector has several drawbacks. First, the exterior of most elbow connectors is made of a conductive or semi-conductive rubber so that the elbow connector can drain off a charge and be at ground potential. The rubber is made conductive by adding carbon black to it. One side effect of adding carbon black to rubber is that it makes the rubber extremely stiff. This side effect is beneficial for the elbow connector because it provides added strength to the elbow connector thereby reducing cracking or tearing along the pulling eye and other stress points of the elbow connector when the connector is being attached or detached from the bushing. By making the jacket sleeve from the same material the jacket sleeve is stiff and not pliable. The stiffer jacket sleeve is difficult to get over the exposed portion of the cable, once mastic and/or tape has been applied because the sleeve does not stretch well but still must have an interference fit with the tape or mastic covering the exposed portion of the cable.
Another problem with the combination jacket sleeve and elbow connector is that the small tabs provided along the edge of the jacket sleeve are not sufficient to assist in grasping and pulling the jacket sleeve over the tape and mastic. When connecting cable to the elbow connectors and the elbow connectors to the switchgear or transformer, a lineperson must apply layers of grease to each of the connecting bodies. As a function of the application, a lineperson frequently gets grease on their hands, making it difficult to grasp and hold onto the small tabs provided on the jacket sleeve.
Yet another problem with the combination jacket sleeve and elbow connector is that, the window for error in building up the protective layers of tape and mastic on the exposed portion of the cable is substantially less with the stiffer material being used for the jacket sleeve. Mastic is a gooey adhesive (and in some forms a tape), similar to putty, that bonds to itself and provides a water barrier for the exposed portion of the cable. Unfortunately, mastic tends to become loose and runny under extreme heat and comes off of the cable if it is not held in place. Therefore, electrical tape is typically applied over the mastic in several layers to hold the mastic in place and provide compression. The jacket sleeve generally has an inside diameter that is greater than the cable so that the layer of mastic and tape may be applied and an interference fit with the tape can be created. However, the stiffer the sleeve is, the less a lineperson will be able to get the sleeve over tape that has a diameter that is a little too large.
In view of the foregoing there is a need in the art for a jacket sleeve that may be made integrally with or subsequently affixed to a connector, whereby the jacket sleeve is made of a material that is more pliable than the connector. Furthermore, there is a need in the art for a jacket sleeve that provides an improved method for grasping and pulling the sleeve over the tape, mastic and exposed portions of the cable. Furthermore there is a need in the art for a method of manufacturing a jacket sleeve either integrally or separate from an electrical connector whereby the sleeve is made of a material that is more pliable than the material from which the electrical connector is made.